Parker Semin, a 2011 Arapahoe High School graduate, prays at a makeshift memorial bearing the name of wounded student Claire Davis, who was shot by a classmate during school three days earlier in an attack, in front of Arapahoe High School in Centennial, Colo., Monday, Dec. 16, 2013. Semin said he came by to pray for the "speedy recovery" of Davis, age 17, who was shot in the head at close range with a shotgun, and remains in a coma. (AP Photo/Brennan Linsley)

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Claire Esther Davis, who was shot at a Colorado high school, remains in a coma—five days after the incident.

CENTENNIAL, Colo. (AP) — The Colorado high school student who critically wounded a classmate before killing himself on Friday may have planned to attack five rooms inside the school, a sheriff said.

Karl Pierson, 18, had letters and numbers corresponding to the Arapahoe High School library and four adjacent classrooms written in indelible marker on a forearm, Arapahoe County Sheriff Grayson Robinson said Tuesday.

Investigators were trying to determine whether Pierson intended to attack the occupants of those rooms, Robinson said in a statement.

Also written on Pierson’s arm was the Latin phrase, “Alea iacta est,” which translates to “The die has been cast,” Robinson said.

Robinson has previously said that investigators believed a librarian who headed the school’s speech and debate team was Pierson’s intended target Friday, but that Pierson also planned to harm many others. Pierson had been disciplined by the debate team coach in September.

The librarian escaped, but Pierson critically wounded a 17-year-old senior, Claire Davis, whom he encountered when he entered the school. Davis remains in a coma at Littleton Adventist Hospital.

Pierson, a senior, killed himself in the library 80 seconds after entering the school as a school security officer closed in.

He was armed with a 12-gauge pump-action shotgun, more than 125 rounds of buckshot, steel-shot and slug ammunition, three Molotov cocktails and a machete, Robinson said.

Earlier AP update:

CENTENNIAL, Colo. (AP) — Support and concern for a 17-year-old girl critically wounded by a fellow student at a suburban Denver high school poured in Monday, both online and outside the school.

People offered prayers and left notes of support for Claire Davis at a fence at Arapahoe High School where white cups spelled out “Pray 4 Claire (heart)” A notebook and a Christmas stocking filled with pens hung from the fence, while others left stuffed animal horses because of her love of riding.

School graduate Parker Semin, 21, said he knelt in front of the fence to pray for a speedy recovery.

On Twitter, people offered prayers in several languages for Davis, who is in a coma at a hospital a couple of miles away from the school.

Hundreds of students and other supporters turned out at the school’s track on Sunday to pray and show support for Davis, described as fun, bubbly and caring.

“She is someone we need back, and we’re hoping she gets better because Arapahoe won’t be the same without her,” LinsiAn Loadman-Copeland said.

Maggie Hurlbut recalled how she was upset in the hallway at school once and Davis, whom she didn’t know very well, stopped to ask her how she was doing and offer help.

“She just wants to take care of others,” she said.

Authorities believe she was shot at random by fellow senior Karl Pierson soon after he entered the school Friday armed with a shotgun, extra ammunition, a machete and three Molotov cocktails, looking for a faculty member with whom he had a dispute. Davis was sitting with a friend near the school library when Pierson shot her in the head point blank.

In their first comments since the shooting, Pierson’s parents said they were shattered and devastated by the shooting and offered their thoughts and prayers for Davis, her family and the entire school community.

“As parents, we loved our son Karl dearly and we are devastated by what happened Friday. We cannot begin to understand why Karl did what he did,” Barbara and Mark Pierson said in a statement.

Pierson may have been nursing a grudge against a school librarian who coached the speech and debate team since September. Pierson excelled at speech and debate and was passionate about the team, friends said. They described him as a smart student who sometimes would get into debates with his teachers.

Pierson had been disciplined by the librarian for reasons yet to be disclosed, according to Arapahoe County Sheriff Grayson Robinson. He has said Pierson threatened that teacher in September and came to the school Friday intending to harm him and inflict numerous other casualties.

The coroner confirmed Monday that Pierson committed suicide by shooting himself in the head. Robinson said Pierson killed himself 80 seconds after entering the school because he knew a deputy assigned to the school was closing in.

The investigation into the shooting continues, but authorities have finished their examination of the school building. Students will be allowed back later in the week to get their belongings, but with the holiday break scheduled for next week, they won’t be returning to class until January.

Why would any sane person sell weapons to a left-wing nut job that had such radical views? Karl Pierson was nothing more than another James Holmes, a Coward. I Hope Clair pulls through, but it looks like its going to be a long road to recovery. I would put the blame on the parents of Pierson because they obviously didn’t raise their son properly and are the type of people that should have never had children. I think Civil Charges should be brought against the Parents.

Another Opinionated Person

Please think before you speak, because you sound very ignorant. The parents can’t control every second of their 18-year-old son’s life. If he exhibited problematic behavior at home, I am sure that they would have taken action upon that. This incident was far beyond their control.